Coil carrier means in an electronic timepiece movement

ABSTRACT

In an electronic timepiece the electromagnet coils which cooperate with the movable magnets mounted on the balance wheel are mounted on a frame pivoted to the base of the timepiece so as to arrange the coils for movement into and out of operative relation with the magnets. The electrical connections for the coils are made thru complimentary sliding contact members mounted about the pivot point for the frame.

United States Patent Inoki et al.

COIL CARRIER MEANS IN AN ELECTRONIC TIMEPIECE MOVEMENT Inventors:Kazuyoshi Inoki; Yasuaki Nakayama, both of Tokyo, Japan Citizen WatchCompany, Limited, Tokyo, Japan Filed: Nov. 10, 1970 Appl. No.: 88,431

Assignee:

Foreign Application Priority Data Nov. I0, 1969 Japan ..44/10662O US.Cl. ..58/23, 58/28 A Int. Cl. ..G04c 3/00, G04c 3/00 Field oiSearch..58/23, 23 A, 23 BA, 23 TF,

3,653,199 [45] Apr. 4, 1972 [56] References Cited FOREIGN PATENTS ORAPPLICATIONS 1,473,362 2/l966 France ..58/23 A Primary Examiner-RichardB. Wilkinson Assistant Examiner-Edith C. Simmons AttorneySughrue,Rothwell, Mion, Zinn & Macpeak [5 7] ABSTRACT In an electronic timepiecethe electromagnet coils which cooperate with the movable magnets mountedon the balance wheel are mounted on a frame pivoted to the base of thetimepiece so as to arrange the coils for movement into and out ofoperative relation with the magnets. The electrical connections for thecoils are made thru complimentary sliding contact members mounted aboutthe pivot point for the frame.

5 Claims, 9 Drawing Figures v PATEMTEBAPR 4 m2 sum 2 [IF 4 FIG. 3A

COIL CARRIER MEANS IN AN ELECTRONIC TIMEPIECE MOVEMENT This inventionrelates generally to improvements in and relating to battery-drivenelectronic timepieces comprising movable magnet means and stationarycoil means relative to the casing of the timepiece and arranged toelectromagnetically cooperating with each other. More specifically, itconcerns with a device for mounting the normally stationary coil means.

In this conventional type of electronic timepiece, it is arepresentative arrangement that the movable magnets are mounted on thebalance wheel comprised in the timepiece movement and the stationarycoil or coils are mounted on a certain support means which is mounted inturn on the housing of the timepiece, said coil or coils beingpositioned between the two balance wheels of the balancer maintainingsmall gaps between the coil means and the balance wheels for allowingtheir relative movement and for obtaining a maximum possible conversionefficiency.

Even upon assembly of the magnet-carrying balance wheel into thetimepiece movement, a redismantling job thereof may frequently berequired for performing various and mostly delicate mechanicalcorrections.

As an example, the oscillation movement of the balance wheel may befound as defective so that the mechanical feed through thetime-indicating gear train is out of order. On the other hand, the hairspring may be defective or at least in a fouled condition so that acorrection and/or purification job is required. For performing suchcorrection or other job, the balance wheel must be dismantled from itsassembled position. In each time for performing the balance wheeldismantling job, the coil carrier must also be dismantled from thetimepiece movement which means naturally a troublesome and costlyadditional job.

As is commonly known, the balance wheel is so delicate that it must beassembled or dismantled with highest care and caution. On the otherhand, the sensing and drive coils used for the electronic timepiece arecomposed of very fine gauge wires, such as, of 15 microns, and thus,fatal wire breakages may be always feared in the course of the balancewheel dismantling job, even when the sincerest caution has been paidtherefor.

The main object of the present invention is to provide an improvedelectronic timepiece, capable of substantially obviating theaforementioned conventional drawbacks.

A further object is to provide an improved electronic timepiece of thetype wherein fear of coil breakage can be avoided in case of recedingand re-attaching the coil means thereof from and to the operatingposition relative to the timepiece movement.

For fulfilment of the aforementioned object the basic and novel teachingof the present invention resides in such improved structure of thecoil-carrying means that by loosening the fixing screw for the latterand swivelling the carrying means together with the mounted coil orcoils to a sufficiently off-set position, the balance wheel or the liketimebase and electromagnetic drive means can be brought into itsready-fordismantling position from the timepiece movement.

These and further objects, features and advantages of the invention willbecome more apparent when read the following detailed description of theinvention by reference to the accompanying drawings illustrative ofseveral preferred embodiments of the invention.

In the drawings:

FIG. 1 is a plan view of a part of a timepiece movement provided with apivotable coil carrier according to a first embodiment of the invention.

FIG. 2 is a schematic wiring diagram of the electronic circuit embodiedin the first embodiment.

FIGS. 3 and 3A is a sectional view taken substantially along the sectionline Ill-Ill in FIG. 1.

FIG. 4 is a similar view to FIG. 1, showing a second embodiment of theinvention.

FIGS. 5 and 5A are an enlarged sectional view taken substantially alongthe section line V-V shown in FIG. 4.

FIG. 6 is a plan view of a part of a third embodiment of the invention.

FIG. 7 is a sectional view of the third embodiment shown in FIG. 6,being taken substantially along a section line VII-VII shown therein.

Referring now to FIGS. 1 3 and 3A, the first embodiment will bedescribed in detail.

In these figures, numeral 1a and lb denote a pair of balance wheels of aconventional balance shown generally at l which wheels are fixedlyattached to an oscillatable staff 2 rotatably mounted at its upper andlower ends as known per se in respective conventional bearings 3 and 4.The upper bearing 3 is designed as a conventional shock-proof type andthe lower bearing 4 is designed as a conventional plain thrust andradial combined type, as will be moist clearly seen from FIGS. 3 and 3Awhich has been drawn on a slightly enlarged scale only for clarity anddivided into two upper and lower parts to be conjoined together at apartition line A-A'. The lower bearing is mounted in a conventionalplate 5 of the timepiece movement, not shown, said plate mounting abalance bridge 6 rigidly attached thereto by means of a pair of setscrews 7 and 8 shown in Fig. l.

The shock-proof type upper bearing 3 is assembled with a conventionalfine-adjusting regulator 9 having fork arms 9a and 9b which are kept inengagement with an adjusting screw 10 studded on the balance bridge 6and formed with an eccentric head 10a for adjusting the oscillatingfrequency of the balance 1 through the regulator as known per se. Thefine-adjusting regulator 9 mounts elastically a conventional regulatorproper 11 carrying rigidly boot 12 and curb pin 13. Numeral 14 denotes aconventional hair spring stud carrier which is elastically attached to acasing frame 15 of the shock proofer generally shown at 16 for thebalance staff 2 as conventionally. The shock-proofer 16 is of theconventional single cone type as seen from FIGS. 3 and 3A which is showninto two parts only for drawing convenience; said parts are to be joinedtogether along the partition line A-A'. Numeral 1411 represents thestud.

Balance wheel staff 2 mounts fixedly a collet 17 attached by press fitthereto and carrying the outer end of a hair spring 18 shown onlyschematically.

Balance wheels la and 1b are mounted on the staff 2 by means ofrespective mounts 19a and 19b press-fit thereon, the upper mount 19abeing positioned directly below the collet 17.

A pair of permanent magnets 20a and 20b is fixedly attached on to thelower surface of the upper balance wheel 1a 1 and a further pair ofpermanent magnets 20c and 20d is fixedly mounted on the upper surface ofthe lower balance wheel lb, magnets 20a and 20b being positioned in avertical registration with each other, as shown in FIGS. 3 and 3A; asimilar registration can be found between the remaining magnets 20b and200 in the same figure.

Nearly at the lower end of the balance staff 2, a conventional roller 21is mounted fixedly thereon and an impulse pin 22 fixedly depends fromthe roller 21, so as to actuate upon a conventional escapement 23 shownonly partially and schematically on account of its very popularity.

Lower plate 5 is made of a conducting material and serves as the earthconductor for an electronic sensing and drive circuit shown in Fig. 2only in its main constituents.

Sensing and driving coils 24 and 25 are mounted on a pivotable supportlever 26, being made of an insulating material, by partially insertingsnugly into a recess 26;: and held in position by glueing. This supportlever 26 thus, constitutes a kind of an elongated frame member and isnormally fixed in its operating position shown in FIGS. 3 and 3A bymeans of a pair of fixing bolts 27 and 28 which are screwed intopartially tapped holes 29 and 30 in the lower plate 5 and havingrespective threaded bore parts 29a and 30a, respectively. For thispurpose, the lever 26 is formed with a boltreceiving opening 61 for thelatter bolt 28 and a stepped bolt hole 32 for the former bolt 27. Thepositioning level of the coils 24 and 25 is so selected that in theirworking position shown in Fig. 3, they are positioned between the magnetpairs 20a; 20c and 20b; 20d with small idle gaps denoted by referencesymbols g.

In Fig. l, coils 24 and 25 and their carrier lever 26 are shown, on theone hand, in full lines, so long as they may be seen from above in theiroperating position, and shown, on the other hand, in chain dotted lineswhen they are swivelled out about its pivot bolt 27 into theiroff-service position for allowing easy dismantling the balance wheelassembly. These chaindotted position is shown with corresponding samereference numerals, each being, however, attached with a prime for easycomparison and prompt understanding.

Bolt 28 is formed with an enlarged head 28a and a connecting terminal 31is kept in pressure contact between bolt head 28a and the upper surfaceof support lever 26 when the related bolt 28 has been tightly screwedin, for providing earth connection from the circuit shown in Fig. 2 tothe lower plate 5.

In the circuit shown in Fig. 2, there are provided sensing coil 24 anddrive coil 25, each of one end being earthed through said connectingterminal 31. The opposite end of coil 24 is connected through terminalcontacts 39 and 40, and adjustable resistor 62 and a condenser 63 to ajunction 64 which is earthed through a fixed resistor 33 and saidterminal 31, said junction 64 being connected to the base of anamplifier transistor 34.

Collector of the transistor 34 is connected through an adjustableresistor 37 to the opposite end of the drive coil 25, while emitter ofthe transistor 34 is earthed through battery 35 and main switch 36 tothe terminal 31 (Fig. 3) as the earth conductor.

A flanged first insulator sleeve 38 encloses concentrically asubstantial upper part of bolt 27 and is rotatably supported at itslower end in the lower reduced part of the stepped opening 32. Below theupper end flange of insulator sleeve 38, there is provided said terminal39 which is kept in pressure and conductive contact with a furtherterminal 40 for establishing an electrical connection between theseterminals. A second flanged insulator sleeve 41 is mounted around thefirst insulator for keeping the both terminals in position around thebolt 27, on the one hand, and said further pair of connection terminals42 and 43 to be held in position between the head flange 44a of sleeve44 and the upper surface of the plate when the pivot bolt 27 has beentightened as shown, on the other hand. The lower end of first sleeve 38is recessed at 38a with which a projection 65 formed on the lever 26 iskept in a mutually engaging position, so as to prevent any turning ofthe sleeve 38. Connecting terminals 39 and 43 are preferably fixedlyattached, for instance, by glueing to the first insulator sleeve 38 andthe coil carrier lever 26, respectively, for avoiding otherwise possiblebreakage of the fine coil wires in case of swivelling movement of thepivotable lever 26.

The operation of the electronic timepiece proper is substantiallysimilar to those which have been commonly used.

For initiating the oscillating movement of the balance, switch 36 isclosed. In this case, normally, magnets a-20d are positioned somewhatoff-set position from that shown in Figs. 1, 3 and 3A in accordance withthe initial design condition of the present electronic timepiece. Then,current is supplied from battery 35 to transistor 34, thence throughvariable resistor 37 and drive coil 25, thereby magnets 20a and 20cbeing electromagnetically attracted for initiation of the oscillation ofthe balance.

During oscillation, the magnets 20b and 20d are correspondingly movedand currents are induced in the sensing coil 24 and transmitted to thetransistor 34, thus the amplified current being fed to the drive coilfor maintaining the balance oscillation and so on. Motion is thustransmitted from the impulse pin 22 to the escapement 23, so as to drivethe time-indicating gear train, not shown of the timepiece, and so Whenit is desired to recede the coils 24, 25 and its carrier lever 26 fromtheir working position to their off-service position shown in Fig. l bychain-dotted lines, switch 36 is opened and coil-carrying lever 26 ispivoted outwardly and manually by a proper tool, upon loosening the bothattaching bolts 27 and 28. By loosening the bolt 27 as aforementioned,first insulator sleeve 38 is loosened and coil-side terminals 39 and 43become loosened relative to the respectively mating terminals 40 and 42.Rotation of coil-carrying lever 26 will accompany the first insulatorsleeve 38, thus the terminals 39 and 43 being rotated in unison with thelever 26. This feature contributes substantially for the prevention ofotherwise possible coil wire breakage in case of the receding movementof the lever 26 together with the coils 24 and 25.

Main components such as 33-35 of the circuit shown in Fig. 2 areembodied into a rigid mass, and indeed, in a mass of synthetic resin, soas to provide a circuit block, although not shown. The relativelyrotatable construction of the circuit-side terminal 40 and 42 willcontribute naturally for the same purpose to avoid otherwise possiblewire breakage.

A return movement of the coils from their off-service position to theiroperating position can be performed in the reverse order. In this case,also, the fear of wire breakage can be avoided in the similar manner.

Although the foregoing description had been substantially directed to abalance wheel type electronic timepiece, the invention can be equallyapplied to other kinds of electronic timepieces for receding easily andconveniently the coils and coil-carrying member, so as to provide achance for easy and safe dismantling of the magnet-carrying member ormembers in the similar manner, and with assurance of the prevention ofotherwise possible coil wire breakage.

In a modification to be described, said coils are united into one piece,preferably in the form of a disc. In this case, two pairs of connectionterminals may be reduced to only a pair.

Next, referring to Figs. 4, 5 and 5A, the second embodiment of theinvention will be described in detail. It should be, however, noted thatsimilar parts of the present embodiment to those in the foregoing firstembodiment are denoted respective same reference numerals added eachwith 100.

In this second embodiment, the number of coils has been reduced to onlyone or more specifically to that denoted 124. This single coil 124 hasbeen shaped into a disc which comprises two sensing anddrive coilelements united into one piece, although not specifically shown. Inresponse thereto,

the number of permanent magnets has been reduced to only two, or morespecifically to those denoted a and 1200 In place of the permanentmagnets 12% and 120d, the balance wheels 101a and 1011) are formedrespectively with counter or galance weight parts 101a and 101b' forattaining a favorable dynamic balance.

In the present embodiment, the fixing bolt 28 employed in the foregoingembodiment has been dispensed with. The earth terminal 131 whichcorresponds to that 31 in the first embodiment, is positioned underneaththe blot head 127a of bolt 127. It should be noted that the bolt 127 hasleft-handed threads, so as to make the tightening direction of the boltcoincident of the direction of return pivoting direction of the coilcarrier lever 126 from its off-service to its operating position. Thus,the tightening operation on the bolt 127 will automatically swivel thelever 126 from its off-service to its operating position. Undercircumstances, a slight manual assistance may-be required additionallyfor doing the lever-return operation. Conversely, the looseningoperation on the bolt 127 will bring the lever 126 to swivel from itsoperating position to its offservice one. But, under certain occasion, aslight manual assistance may be required to initiate or accelerate theleverreceding operation.

The electronic drive circuit employable in the present second embodimentis similar in its principle to that shown in Fig. 2. As was referred tohereinbefore, sensing and drive coils 24 and 25 have been embodied intotwo coil elements, not shown, which has been formed into the single disccoil assembly 124 shown schematically in Figs. 4 and 5. In the presentcase, the earth connection from the sensing and drive circuit to thelower plate 105 is made through the connecting terminal and the pivotbolt 127.

'Further operation of the present embodiment is substantially similar tothat of the first embodiment.

Next, referring to Figs. 6 and 7, the third embodiment will be describedin detail. In this embodiment, the fixing screw 28 employed in the firstembodiment has been again dispensed with, and, as in the case of theforegoing second embodiment, sensing and drive coils have been embodiedin a single disc coil assembly 224. It should be noted that in theseFigs. 6 and 7, similar parts to those employed in the first embodimentare denoted respective same reference numerals, each thereof, howeverbeing added with 200, irrespective of occasional difference in theirphysical configuration.

In Figs. 6 and 7, the single coil assembly 224 is fixedly mounted on acarrier member formed again into a pivotable lever 226 about the pivotbolt 227 which is held in position in the similar way as disclosed withreference to the second embodiment. On the upper surface of this lever226e, three conductor strips 71, 72 and 73 having respective connectingterminals 71a, 72a and 73a are formed by the printed circuit technology,said terminals being electrically connected by respective leads 74, 75,76 and 77 with respective wire ends, not shown, of coil elements 224aand 22412 of the disc coil assembly 224. These coil elements 224a and224b correspond in principle in their function and electric connectionmode to those denoted 24 and 25 in the first embodiment. The respectiveright-hand ends of these strips 71 and 73 are kept in pres sure contactwith the respective inner mating strips 78 and 80 form on the backsurface of a flexible insulator sheet 81 connected mechanically with themolded circuit block embedded therein with several circuit elements 3234, said block being fixedly mounted on he plate 205, although notshown. This lastmentioned feature is also employed in the foregoingfirst and second embodiments. The strips 78 and 80 are connectedrespective points such as shown at 40 and 42 of the circuit shown in Fig2. The right-hand end of the central conductor 72 is formed into aconductive spring washer 231 which is mounted under pressure between thebolt head 227a and the printed conductive strips 71-73 formed of thecoil carrier lever 226 and around the latter in conductive contacttherewith. The washer 231 is positioned within a bore 227b formedthrough the flexible carrier sheet 81. By this arrangement, asatisfactory earth connection is provided between the coil assembly 224and the plate 205 further through the pivot bolt 227.

Adjustable resistor 37 serves as a manual adjuster for modifying theoscillation angle of the balance, as at 1 shown in the first embodiment,although not shown in the present embodiment only for simplicity.

For maintaining the coil carrier 226 in the required operating positionrelative to the plate 205, a proper stopper pin, not shown, on the plate205.

As will be easily understood from the foregoing, it would be clear thatthe pivotable function for attaining the desired objects of theinvention is substantially similar to that of the second embodiment.

What is claimed is 1. In an electronic timepiece having frame means,movable magnet means, carrier means and coil means mounted on saidcarrier means for electromagnetic cooperation with said magnet means,the improvements comprising pivot means for pivotally mounting saidcarrier means on said frame means for movement between a first positionlocating said coil means in operative position relative to said movablemagnet means and a second position to facilitate servicing, and slidingelectrical connection means for said coils disposed adjacent said pivotmeans.

2. In an electronic timepiece as set forth in claim 1 wherein said coilmeans is comprised of two separate coils, and said electrical connectionmeans is comprised of at least one movable electricalcontact connectedto each coil and mounted for movement with said carrier means ad acentsaid pivot means and a plurality of stationary electrical contactsmounted adjacent said pivot means and disposed in sliding engagementwith each of said movable electrical contacts.

3. In an electronic timepiece as set forth in claim 1 wherein said coilmeans is comprised of a single coil having a driving and sensing portionand each electrical connection means is comprised of at least onemovable electrical contact connected to each position of said coil andmounted for movement with said carrier means adjacent said pivot meansand disposed in sliding engagement with each of said movable electricalcontacts.

4. In an electronic timepiece as set forth in claim I wherein threecontact strips electrically connected to said coil means are mounted onsaid carrier means substantially parallel to each other with the middlestrip thereof intersecting the pivot means, support means overlying saidcarrier means and provided with three additional contact stripssuperimposed in sliding contact on the three contact strips n saidcarrier.

means, said middle strips being electrically connected to said pivotmeans.

5. In an electronic timepiece as set forth in claim 4 wherein saidsupport means in a flexible strip.

1. In an electronic timepiece having frame means, movable magnet means,carrier means and coil means mounted on said carrier means forelectromagnetic cooperation with said magnet means, the improvementscomprising pivot means for pivotally mounting said carrier means on saidframe means for movement between a first position locating said coilmeans in operative position relative to said movable magnet means and asecond position to facilitate servicing, and sliding electricalconnection means for said coils disposed adjacent said pivot means. 2.In an electronic timepiece as set forth in claim 1 wherein said coilmeans is comprised of two separate coils, and said electrical connectionmeans is comprised of at least one movable electrical contact connectedto each coil and mounted for movement with said carrier means adjacentsaid pivot means and a plurality of stationary electrical contactsmounted adjacent said pivot means and disposed in sliding engagementwith each of said movable electrical contacts.
 3. In an electronictimepiece as set forth in claim 1 wherein said coil means is comprisedof a single coil having a driving and sensing portion and eachelectrical connection means is comprised of at least one movableelectrical contact connected to each position of said coil and mountedfor movement with said carrier means adjacent said pivot means anddisposed in sliding engagement with each of said movable electricalcontacts.
 4. In an electronic timepiece as set forth in claim 1 whereinthree contact strips electrically connected to said coil means aremounted on said carrier means substantially parallel to each other withthe middle strip thereof intersecting the pivot means, support meansoverlying said carrier means and provided with three additional contactstrips superimposed in sliding contact on the three contact strips nsaid carrier means, said middle strips being electrically connected tosaid pivot means.
 5. In an electronic timepiece as set forth in claim 4wherein said support means in a flexible strip.